Systems, devices, and methods for packet data convergence protocol packet data unit duplication

ABSTRACT

A method by a wireless communication network for handling one or more duplicated packet data convergence protocol (PDCP) packets is described. The method includes sending, by a master node, a request for a configuration for duplication to a secondary node, and providing, by a secondary node, a mapping configuration for duplication in a secondary cell group (SCG) to a user equipment (UE).

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a divisional application of U.S. patent applicationSer. No. 16/015,229 filed Jun. 22, 2018, which claims the benefit of andpriority to provisional U.S. Patent Application Ser. No. 62/523,367filed Jun. 22, 2017. The contents of all above-named applications arefully incorporated herein by reference for all purposes.

FIELD

The present disclosure generally relates to wireless communicationsystems. More specifically, the present disclosure relates to systems,devices, and methods for mapping configurations and resourceconfigurations for Packet Data Convergence Protocol (PDCP) Packet DataUnit (PDU) Duplication (hereinafter also referred to as “Duplication”).

BACKGROUND

Various efforts have been made to improve the performances of wirelesscommunications, such as data rate, latency, reliability, mobility andetc., for the next generation (e.g., 5G) wireless communicationnetworks. Among the goals, the next generation wireless communicationnetworks are expected to provide high reliability for ultra-reliable lowlatency communication (URLLC) service while under strict latencyrequirements.

Although according to the 3rd Generation Partnership Project (3GPP)Technical Report (TR) 38.804, PDCP PDU Duplication under carrieraggregation (CA), dual-connectivity (DC), and multi-connectivity (MC)operations will be supported for Data Radio Bearers (DRBs) and SignalingRadio Bearers (SRBs), the details on how to apply PDCP PDU duplication(e.g., uplink and downlink Duplications) have not been extensivelydiscussed.

Thus, there is a need in the art for efficient systems, devices, andmethods for PDCP PDU duplication.

SUMMARY

The present disclosure is directed to systems, methods, and devices forPDCP PDU duplication.

According to a first aspect of the present disclosure a method for auser equipment (UE) to deliver one or more duplicated packet dataconvergence protocol (PDCP) packets of a radio bearer is disclosed, themethod comprising: selecting at least one physical radio resource blockon one or more allowed serving cells to deliver the one or moreduplicated PDCP packets after receiving an activation message of packetduplication to activate at least one logical channel corresponding tothe radio bearer to deliver the one or more duplicated PDCP packets;stopping applying the one or more allowed serving cells to the at leastone logical channel when receiving a deactivation message of packetduplication.

In an implementation of the first aspect, the method further comprises:receiving, by the UE, a mapping configuration from a base station; wherethe one or more allowed serving cells are configured by the base stationbased on the mapping configuration, and the mapping configurationprovides mapping rules between logical channels and serving cells toindicate one or more indices of the one or more allowed serving cells ofthe at least one logical channel through which the UE is allowed todeliver the one or more duplicated PDCP packets.

In another implementation of the first aspect, the mapping rules includeat least one Serving Cell index corresponding to at least one of the oneor more allowed serving cells in the mapping configuration.

In yet another implementation of the first aspect, the Serving Cellindex value=0 is mapped to a special cell of a cell group correspondingto the at least one logical channel, the special cell is a primary cell(PCell) in a master cell group (MCG) or a primary secondary cell(PSCell) in a secondary cell group (SCG).

In yet another implementation of the first aspect, the at least onelogical channel is configured with at least one of the one or moreallowed serving cells, wherein the one or more allowed serving cells areassociated with one or more serving cell groups.

In yet another implementation of the first aspect, the at least onelogical channel is configured with at least one of the one or moreallowed serving cells, wherein the one or more allowed serving cells areassociated with a master cell group and at least one secondary cellgroup.

In yet another implementation of the first aspect, the mappingconfiguration is provided by the special cell of the cell groupcorresponding to the at least one logical channel, the special cell isthe PCell in the MCG or the PSCell in the SCG.

In yet another implementation of the first aspect, the method furthercomprises selecting or re-selecting, by the UE, at least another servingcell to deliver the one or more duplicated PDCP packets based on one ormore predefined triggering events.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is related to channel qualities of theone or more allowed serving cells.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is based onacknowledgement/non-acknowledgement (ACK/NACK) responses of PDCP packetdelivery in each of the one or more allowed serving cells.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is based on a channel occupancy ratioof shared radio resource among UEs in each of the one or more allowedserving cells.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is based on a buffer status of the oneor more duplicated PDCP packets associated with the at least one logicalchannel configured for PDCP packet delivery.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is based on deactivation of at leastone of the one or more allowed serving cells.

In yet another implementation of the first aspect, one of the one ormore predefined triggering events is based on a radio link failure to acell group of the one or more allowed serving cells.

In yet another implementation of the first aspect, the method furthercomprises: disabling a de-activation timer of at least one of the one ormore allowed serving cells after receiving the activation message ofpacket duplication; enabling the disabled de-activation timer afterreceiving a deactivation message of packet duplication.

In yet another implementation of the first aspect, the method furthercomprises: sending a special buffer status report to a base station foran uplink (UL) grant request to transmit the one or more duplicated PDCPpackets.

In a second aspect of the present disclosure, a user equipment (UE) isdisclosed, the UE comprising: one or more processors; one or morenon-transitory, computer-readable media, coupled with the one or moreprocessors, having executable instructions embodied thereon, which, whenexecuted by the one or more processors cause the one or more processorsto perform operations comprising: selecting at least one physical radioresource block on one or more allowed serving cells to deliver one ormore duplicate packet data convergence protocol (PDCP) packets of aradio bearer after receiving an activation message of packet duplicationto activate at least one logical channel corresponding to the radiobearer to deliver the one or more duplicate PDCP packets; stoppingapplying the one or more allowed serving cells to the at least onelogical channel when receiving a deactivation message of packetduplication.

In an implementation of the second aspect, the executable instructions,when executed by the one or more processors, cause the one or moreprocessors to further perform operations comprising: receiving a mappingconfiguration from a base station; wherein the one or more allowedserving cells are configured by the base station based on the mappingconfiguration, and the mapping configuration provides mapping rulesbetween logical channels and serving cells to indicate one or moreindices of the one or more allowed serving cells of the at least onelogical channel through which the UE is allowed to deliver the one ormore duplicate PDCP packets.

In another implementation of the second aspect, the mapping rulesinclude at least one SCell index corresponding to at least one of theone or more allowed serving cells in the mapping configuration.

In yet another implementation of the second aspect, the at least onelogical channel is configured with at least one of the one or moreallowed serving cells, wherein the one or more allowed serving cells areassociated with one or more serving cell groups.

In yet another implementation of the second aspect, the at least onelogical channel is configured with at least one of the one or moreallowed serving cells, wherein the one or more allowed serving cells areassociated with a master cell group and at least one secondary cellgroup.

In yet another implementation of the second aspect, the mappingconfiguration is provided by a primary cell of the master cell group.

In yet another implementation of the second aspect, the mappingconfiguration is provided by a primary secondary cell of the at leastone secondary cell group.

In yet another implementation of the second aspect, the executableinstructions, when executed by the one or more processors, cause the oneor more processors to further perform operations comprising: selectingor re-selecting, by the UE, at least another serving cell to deliver theone or more duplicate PDCP packets based on one or more predefinedtriggering events.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is related to channel qualities of theone or more allowed serving cells.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is based onacknowledgement/non-acknowledgement (ACK/NACK) responses of PDCP packetdelivery in each of the one or more allowed serving cells.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is based on a channel occupancy ratioof shared radio resource among UEs in each of the one or more allowedserving cells.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is based on a buffer status of theduplicate PDCP packets associated with the at least one logical channelconfigured for PDCP packet delivery.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is based on deactivation of at leastone of the one or more allowed serving cells.

In yet another implementation of the second aspect, one of the one ormore predefined triggering events is based on a radio link failure to acell group of the one or more allowed serving cells.

In yet another implementation of the second aspect, the executableinstructions, when executed by the one or more processors, cause the oneor more processors to further perform operations comprising: disabling ade-activation timer of at least one of the one or more allowed servingcells after receiving the activation message of packet duplication;enabling the disabled de-activation timer after receiving a deactivationmessage of packet duplication.

In yet another implementation of the second aspect, the executableinstructions, when executed by the one or more processors, cause the oneor more processors to further perform operations comprising: sending aspecial buffer status report to a base station for an uplink (UL) grantrequest to transmit the one or more duplicated PDCP packets.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the exemplary disclosure are best understood from thefollowing detailed description when read with the accompanying figures.Various features are not drawn to scale, dimensions of various featuresmay be arbitrarily increased or reduced for clarity of discussion.

FIG. 1 is a schematic diagram illustrating multi-connectivity,dual-connectivity, and carrier aggregation Duplication operations, inaccordance with an example implementation of the present disclosure.

FIG. 2 is a diagram illustrating signaling for a mapping configurationfor Duplication, in accordance with an example implementation of thepresent disclosure.

FIG. 3A is a diagram illustrating a master node providing a mappingconfiguration for Duplication to a UE, where the mapping configurationincludes mapping rules for MCG and SCGs, in accordance with an exampleimplementation of the present disclosure.

FIG. 3B is a diagram illustrating a master node and two or moresecondary nodes each providing a mapping configuration for Duplicationto a UE, in accordance with an example implementation of the presentdisclosure.

FIG. 3C is a diagram illustrating a master node and two or moresecondary nodes each providing an operation cell indication forDuplication to a UE, in accordance with an example implementation of thepresent disclosure.

FIG. 4 is a diagram showing Implementation#X3 in Table 3, in accordancewith an example implementation of the present disclosure.

FIG. 5A is a diagram showing a method of a UE informing operationcell(s) for Duplication to various network nodes, in accordance with anexample implementation of the present disclosure.

FIG. 5B is a diagram showing a method of a UE informing operationcell(s) for Duplication to various network nodes, in accordance with anexample implementation of the present disclosure.

FIG. 6 is a diagram illustrating an SPS-configuration having theperiodicity provided through Radio Resource Control (RRC) signaling, andresource blocks for SPS resource provided through L1 signaling, inaccordance with an example implementation of the present disclosure.

FIG. 7 is a diagram illustrating a bitmap for representing a resourceconfiguration for Duplication, in accordance with an exampleimplementation of the present disclosure.

FIG. 8 is a diagram illustrating a RAN providing mappings between LCHsand LCGs for BSR, in accordance with an example implementation of thepresent disclosure.

FIG. 9 is a diagram illustrating a special BSR for Duplication, inaccordance with an example implementation of the present disclosure.

FIG. 10 is a diagram illustrating cross-carrier scheduling forDuplication, where the mapping between logical channels and cells arepre-defined by a base station, in accordance with an exampleimplementation of the present disclosure.

FIG. 11 is a block diagram of a node for wireless communication, inaccordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

The following description contains specific information pertaining toexample implementations in the present disclosure. The drawings in thepresent disclosure and their accompanying detailed description aredirected to merely example implementations. However, the presentdisclosure is not limited to merely these example implementations. Othervariations and implementations of the present disclosure will occur tothose skilled in the art. Unless noted otherwise, like or correspondingelements among the figures may be indicated by like or correspondingreference numerals. Moreover, the drawings and illustrations in thepresent disclosure are generally not to scale, and are not intended tocorrespond to actual relative dimensions.

For the purpose of consistency and ease of understanding, like featuresare identified (although, in some examples, not shown) by numerals inthe example figures. However, the features in different implementationsmay be differed in other respects, and thus shall not be narrowlyconfined to what is shown in the figures.

The description uses the phrases “in one implementation,” or “in someimplementations,” which may each refer to one or more of the same ordifferent implementations. The term “coupled” is defined as connected,whether directly or indirectly through intervening components, and isnot necessarily limited to physical connections. The term “comprising,”when utilized, means “including, but not necessarily limited to”; itspecifically indicates open-ended inclusion or membership in theso-described combination, group, series and the equivalent.

Additionally, for the purposes of explanation and non-limitation,specific details, such as functional entities, techniques, protocols,standard, and the like are set forth for providing an understanding ofthe described technology. In other examples, detailed description ofwell-known methods, technologies, system, architectures, and the likeare omitted so as not to obscure the description with unnecessarydetails.

Persons skilled in the art will immediately recognize that any networkfunction(s) or algorithm(s) described in the present disclosure may beimplemented by hardware, software or a combination of software andhardware. Described functions may correspond to modules may be software,hardware, firmware, or any combination thereof. The softwareimplementation may comprise computer executable instructions stored oncomputer readable medium such as memory or other type of storagedevices. For example, one or more microprocessors or general purposecomputers with communication processing capability may be programmedwith corresponding executable instructions and carry out the describednetwork function(s) or algorithm(s). The microprocessors or generalpurpose computers may be formed of applications specific integratedcircuitry (ASIC), programmable logic arrays, and/or using one or moredigital signal processor (DSPs). Although some of the exampleimplementations described in this specification are oriented to softwareinstalled and executing on computer hardware, nevertheless, alternativeexample implementations implemented as firmware or as hardware orcombination of hardware and software are well within the scope of thepresent disclosure.

The computer readable medium includes but is not limited to randomaccess memory (RAM), read only memory (ROM), erasable programmableread-only memory (EPROM), electrically erasable programmable read-onlymemory (EEPROM), flash memory, compact disc read-only memory (CD ROM),magnetic cassettes, magnetic tape, magnetic disk storage, or any otherequivalent medium capable of storing computer-readable instructions.

A radio communication network architecture (e.g., a long term evolution(LTE) system, a LTE-Advanced (L l′E-A) system, or a LTE-Advanced Prosystem) typically includes at least one base station, at least one userequipment (UE), and one or more optional network elements that provideconnection towards a network. The UE communicates with the network(e.g., a core network (CN), an evolved packet core (EPC) network, anEvolved Universal Terrestrial Radio Access network (E-UTRAN), aNext-Generation Core (NGC), 5G Core Network (5GC), or an internet),through a radio access network (RAN) established by the base station.

It should be noted that, in the present disclosure, a UE may include,but is not limited to, a mobile station, a mobile terminal or device, auser communication radio terminal. For example, a UE may be a portableradio equipment, which includes, but is not limited to, a mobile phone,a tablet, a wearable device, a sensor, or a personal digital assistant(PDA) with wireless communication capability. The UE is configured toreceive and transmit signals over an air interface to one or more cellsin a radio access network.

A base station may include, but is not limited to, a node B (NB) as inthe UMTS, an evolved node B (eNB) as in the LTE-A, a radio networkcontroller (RNC) as in the UMTS, a base station controller (BSC) as inthe GSM/GERAN, an NG-eNB as in an E-UTRA base station in connection withthe 5GC, a next generation node B (gNB) as in the 5G-RAN, and any otherapparatus capable of controlling radio communication and managing radioresources within a cell. The base station may connect to serve the oneor more UEs through a radio interface to the network.

A base station may be configured to provide communication servicesaccording to at least one of the following radio access technologies(RATs): Worldwide Interoperability for Microwave Access (WiMAX), GlobalSystem for Mobile communications (GSM, often referred to as 2G), GSMEDGE radio access Network (GERAN), General Packet Radio Service (GRPS),Universal Mobile Telecommunication System (UMTS, often referred to as3G) based on basic wideband-code division multiple access (W-CDMA),high-speed packet access (HSPA), LTE, LTE-A, eLTE (evolved LTE), NewRadio (NR, often referred to as 5G), and/or LTE-A Pro. However, thescope of the present disclosure should not be limited to the abovementioned protocols.

The base station is operable to provide radio coverage to a specificgeographical area using a plurality of cells forming the radio accessnetwork. The base station supports the operations of the cells. Eachcell is operable to provide services to at least one UE within radiocoverage of the cell. More specifically, each cell (often referred to asa serving cell) provides services to serve one or more UEs within thecell's radio coverage, (e.g., each cell schedules the downlink andoptionally uplink resources to at least one UE within the cell's radiocoverage for downlink and optionally uplink packet transmissions). Thebase station can communicate with one or more UEs in the radiocommunication system through the plurality of cells. A cell may allocatesidelink (SL) resources for supporting proximity service (ProSe). Eachcell may have overlapped coverage areas with other cells.

As discussed above, the frame structure for NR is to support flexibleconfigurations for accommodating various next generation (e.g., 5G)communication requirements, such as enhanced mobile broadband (eMBB),massive machine type communication (mMTC), ultra reliable communicationand low latency communication (URLLC), while fulfilling highreliability, high data rate and low latency requirements. The orthogonalfrequency-division multiplexing (OFDM) technology as agreed in 3GPP mayserve as a baseline for NR waveform. The scalable OFDM numerology, suchas the adaptive sub-carrier spacing, the channel bandwidth, and theCyclic Prefix (CP) may be also used. Additionally, two coding schemesare considered for NR: (1) low-density parity-check (LDPC) code and (2)Polar Code. The coding scheme adaption may be configured based on thechannel conditions and/or the service applications.

Moreover, it is also considered that in a transmission time interval TXof a single NR frame, a downlink (DL) transmission data, a guard period,and an uplink (UL) transmission data should at least be included, wherethe respective portions of the DL transmission data, the guard period,the UL transmission data should also be configurable, for example, basedon the network dynamics of NR. In addition, sidelink resource may alsobe provided in a NR frame to support ProSe services.

FIG. 1 is a schematic diagram illustrating multi-connectivity,dual-connectivity, and carrier aggregation Duplication operations,according to various aspects of the present disclosure. In the presentimplementation, the Packet Data Convergence Control (PDCP), Radio LinkControl (RLC), and Medium Access Control (MAC) entities (e.g., layers)as shown in FIG. 1 may be within a transmitter of a UE or a network node(e.g., a base station). The PDCP PDU duplication may be utilized forDRBs and/or SRBs mapped on dedicated traffic channel (DTCH) and/ordedicated control channel (DCCH) types of logical channels. Aduplication function in the PDCP layer of the transmitter may duplicatePDCP PDU packets where the duplicated PDCP PDU packets may be deliveredto at least two radio bearers (e.g., split radio bearers) and thecorresponding logical channels. The selected radio bearers may be in thesame cell group or different cell groups. Also, the MAC entity of eachcell group may multiplex the duplicated packets and put the duplicatedpackets onto multiple component carriers.

In diagram 100 of FIG. 1, when PDCP PDU Duplication is activated basedon a specific event (e.g., an event-based Duplication activation),duplication function 108 in PDCP layer 106 may duplicate one or morePDCP PDU packets from an original PDCP PDU packet, and provide theduplicated PDCP PDU packets (including the original and duplicated PDCPPDU packets) to at least one additional RLC bearer, where each RLCbearer may compose the lower layer portion of the radio bearerconfigurations including the RLC layer and MAC layer (e.g., logicalchannel) configurations. In some implementations, a radio bearer may beconfigured with two or more logical channels. The PDCP PDU packets ofone radio bearer may be delivered through one (pre-configured) RLCbearer when the duplication function of the corresponding radio beareris de-activated and the pre-configured RLC bearer may be pre-configuredto the UE by serving cells through dedicated control signaling. Itshould be noted that, a PDCP PDU packet may be duplicated to severalPDCP PDU packets to one or more additional RLC bearers while theduplication function of the corresponding radio bearer is activated. Inone implementation, as shown in FIG. 1, the duplicated PDCP PDU packetsare sent to one or more RLC bearers (e.g., RLC bearers 112 and 114) inmaster cell group (MCG) 110, one or more RLC bearers (e.g., RLC bearers122 and 124) in secondary cell group (SCG) 120, and/or one or more RLCbearers (e.g., RLC bearers 132 and 134) in another SCG 130. Aftermultiplexing in the MAC layers of the corresponding MCG 110, SCG 120,and SCG 130, the PDCP PDU packets (e.g., having the original andduplicated PDCP PDU packets) are sent through multiple componentcarriers in the one or more cell groups (e.g., MCG 110, SCG 120, and SCG130). These RLC bearers (e.g., RLC bearers 112, 114, 122, 124, 132, and134) may be configured with the configuration of a DRB or a SRB.

In a CA PDCP PDU Duplication operation according to an exampleimplementation of the present disclosure, the duplicated PDCP PDUpackets (e.g., having the original and duplicated PDCP PDU packets) maybe transmitted or received on component carriers in a single cell groupof a network node (e.g., a master network node, such as a master eNB orgNB). For example, with reference to FIG. 1, the duplicated PDCP PDUpackets may be transmitted or received on component carriers CC#j andCC#i through RLC bearers 112 and 114 of MCG 110.

In a DC PDCP PDU Duplication operation according to an exampleimplementation of the present disclosure, the duplicated PDCP PDUpackets (e.g., having the original and duplicated PDCP PDU packets) maybe transmitted or received on component carriers in a master cell groupof a master network node (e.g., a master eNB or gNB) and a secondarycell group of a secondary network node (e.g., a secondary eNB or gNB).For example, with reference to FIG. 1, one of the duplicated PDCP PDUpackets may be transmitted or received on component carrier CC#j or CC#ithrough RLC bearer 112 or 114 of MCG 110, while the other one of theduplicated PDCP PDU packets may be transmitted or received on componentcarrier CC#b or CC#a through RLC bearer 122 or 124 of SCG 120. Inanother example, one of the duplicated PDCP PDU packets may betransmitted or received on component carrier CC#j or CC#i through RLCbearer 112 or 114 of MCG 110, while the other one of the duplicated PDCPPDU packets may be transmitted or received on component carrier CC#f orCC#e through RLC bearer 132 or 134 of SCG 130.

In an MC PDCP PDU Duplication operation according to an exampleimplementation of the present disclosure, the duplicated PDCP PDUpackets (e.g., having the original and duplicated PDCP PDU packets) maybe transmitted or received on component carriers in a master cell groupof a master network node (e.g., a master eNB or gNB) and two or moresecondary cell groups of two or more secondary network nodes (e.g.,secondary eNBs and/or gNBs). For example, with reference to FIG. 1, oneof the PDCP PDU packets may be transmitted or received on componentcarrier CC#j or CC#i through RLC bearer 112 or 114 of MCG 110; anotherone of the duplicated PDCP PDU packets may be transmitted or received oncomponent carrier CC#b or CC#a through RLC bearer 122 or 124 of SCG 120;yet another one of the duplicated PDCP PDU packets may be transmitted orreceived on component carrier CC#f or CC#e through RLC bearer 132 or 134of SCG 130.

It should be understood that, a DC PDCP PDU Duplication operation may beregarded as a special case of the MC PDCP PDU Duplication operation,where the MCG and only one SCG are configured for the UE. Also, the CAPDCP PDU Duplication operation may be regarded as another special caseof the MC PDCP PDU Duplication operation, where only one cell group(e.g., the MCG) is configured for the UE.

In the CA PDCP PDU Duplication operation, a UE is configured with oneprimary component carrier (PCC) and at least one secondary componentcarrier (SCC). In addition, a PCell is a cell operating on the primarycomponent carrier (PCC), while an SCell is a cell operating on asecondary component carrier (SCC). In the DC and MC PDCP PDU Duplicationoperations, in addition to PCell and SCell, a PSCell is an SCG cell isalso configured, where the UE performs (DL/UL) synchronization andcontrol signaling transmission/reception with the PSCell.

Some implementations of the present disclosure are directed to how theduplication function (e.g., duplication function 108) selects the radiobearers for Duplication. As shown in FIG. 1, there are at least 6available RLC bearers to dispatch the duplicated PDCP PDU packets. Thetransmitter of the UE needs to select one or more RLC bearers to deliverthem independently. To assist the transmitter in selecting radio bearersfor Duplication, a base station (e.g., a serving base station) mayprovide dedicated signaling (e.g., an RRCConnectionReConfigurationmessage) to configure the RLC bearers and the corresponding logicalchannels to one radio bearer (e.g., DRB or SRB) of the UE forDuplication.

Some implementations of the present disclosure are directed to how eachMAC entity decides the mapping between logical channel of eachcorresponding RLC bearer and configured component carriers (or servingcell corresponding to each configured component carrier) forDuplication, so that the duplicated PDCP PDU packets can be delivered tothe receiver through the PCell of a MCG, the PSCell of an SCG, and/orthe SCells of the MCG/SCG(s). For example, to achieve frequencydiversity, the MAC entity of each cell group may follow mapping rules toprevent the duplicated PDCP PDU packets from being delivered on a singlecomponent carrier. In one implementation, a base station (e.g., aserving base station) may configure mapping rules between logicalchannels and serving cells for one or more UEs, and send the mappingconfiguration through explicit signaling (hereinafter also referred to“the Base Station Explicit Signaling approach”) for the UEs to follow.In another implementation, the MAC entities in a UE responsible for eachcell group may select and distribute the duplicated PDCP PDU packets todifferent component carriers (or serving cells) based on the UE'smapping rules (hereinafter also referred to “the UE Self-(re)selectionapproach”).

Some implementations of the present disclosure are directed todetermining what radio resources that the transmitter may apply in thecomponent carriers for Duplication.

CASE 1: Mapping Configuration for Duplication

FIG. 2 is a diagram illustrating signaling for a mapping configurationfor Duplication, in accordance with an example implementation of thepresent disclosure. In the present implementation, UE 202 may include atransmitter having PDCP, RLC, and MAC layers with DRB or SRBconfigurations, which are substantially similar to those shown indiagram 100 in FIG. 1.

In diagram 200, in action 210, base station 204 may send a mappingconfiguration for Duplication to UE 202 through dedicated signaling(e.g., RRC signaling). In the present implementation, base station 204may configure a PCell and/or a PSCell and/or one or more SCells (of MCGand/or SCG(s)) for UE 202, and provide the mapping configuration forDuplication to UE 202. The mapping configuration for Duplicationincludes mapping rules, for at least one of the MAC entities of UE 202,between logical channels and serving cells to aid UE 202 in decidingand/or selecting operation cells (and component carriers) fortransmitting or receiving duplicated PDCP PDU packets.

In the present implementation, the Duplication function may remainde-activated for UE 202 upon receiving the mapping configuration forDuplication from base station 204. Base station 204 may deliver anActivation of Duplication message (or an activation message of packetduplication) through dedicated signaling (e.g., by sending a MAC controlelement (CE)) to UE 202. UE 202 may then start Duplication afterreceiving the Activation of Duplication message. As shown in FIG. 2, inaction 220, base station 204 may send an Activation of Duplicationmessage to UE 202 to start/activate Duplication.

In some implementations, the mapping configuration may be configured bybase station 204 for UE 202 to activate Duplication immediately uponreceipt of the mapping configuration. For example, UE 202 may activateDuplication immediately upon receiving the mapping configuration frombase station 204.

In some implementations, the mapping configuration may be configured bybase station 204 to UE 202 for immediate Duplication activation andevent-based re-selection of operation cell(s). For example, UE 202 mayactivate Duplication immediately upon receiving the mappingconfiguration from base station 204, and may re-select the operationcell(s) among the candidate cells configured by base station 204.

In some implementations, base station 204 may configure event-basedactivation triggers in the mapping configuration, such that UE 202 maydecide to activate Duplication by itself based on one or more triggeringevents configured by base station 204.

For the CA PDCP PDU Duplication operation, base station 204 may providesCellIndex(ices) (index(ices) provided by the radio access network (RAN)to represent SCell(s) of UE 202) that may be utilized for Duplication.For the CA PDCP PDU Duplication operation, in some implementations, basestation 204 may indicate different SCells for DL and UL Duplicationprocesses. For example, as shown in Table 1-1, base station 204 mayindicate {sCellIndex#1, sCellIndex#4} for DL Duplication and{sCellIndex#3, sCellIndex#5, sCellIndex#6} for UL Duplication.

TABLE 1-1 Base station configuring different cells for DL and ULDuplications separately. Type LCH <-> Operation Cell DL DuplicationLCH#a sCellIndex#1 LCH#b sCellIndex#4 UL Duplication LCH#i sCellIndex#3LCH#k sCellIndex#5 LCH#l sCellIndex#6

For the CA PDCP PDU Duplication operation, in some implementations, basestation 204 may indicate the same cells for DL and UL Duplicationprocesses. As shown in Table 1-2, {sCellIndex#3, sCellIndex#3} areprovided for both DL and UL Duplications.

TABLE 1-2 Base station configuring the same cells for DL and ULDuplications. Type LCH <-> Operation Cell DL and UL LCH#a sCellIndex#2Duplications LCH#b sCellIndex#3

For the CA PDCP PDU Duplication operation, in some implementations, aPCell may be utilized to deliver duplicated PDCP packets by default.Thus, base station 204 may only need to indicate the additional SCellfor Duplication. In some implementations, base station 204 may need toindicate a PCell in the mapping configuration. The RAN may pre-define aPCell index (e.g., filling in all zeros in the index field) to representthe PCell. In some additional implementations, base station 204 maydefine another Cell index, called ServCellIndex. Base station 204 is toapply ServCellIndex to indicate at least one serving cell for the MACentity (which is responsible to MCG or SCG) on the UE side to decidewhether the pending packets of one logical channel is allowed to betransmitted on a UL grant of the corresponding serving Cell.ServCellIndex is an integer with a range from 0 tomaxNrofServingCells−1, where the maxNrofServingCells is a pre-definedvalue (e.g., an integer) in technical specification to define themaximum number of serving cells which a UE can support (within a cellgroup). In addition, the value of 0 in ServCellIndex is applied toindicate the PCell in the MCG. Moreover, the value 1 tomaxNrofServingCells−1 of ServCellIndex may have one-to-one mapping tothe corresponding SCellIndex, as shown in Table 1-3. It is also notedthat to a logical channel of SCG, the ServCellIndex=0 may be applied toindicate the PSCell in the SCG.

TABLE 1-3 Explicit approach to indicate that a PCell may be utilized forDuplication, where DL and UL Duplications may utilize the same cells.Type LCH <-> Operation Cell DL and UL LCH#a ServCellIndex(=‘0000’(PCell)) Duplications LCH#b ServCellIndex(=sCellIndex#1)

In some implementations, the RAN may configure a list of operationcells, which is called an operation cell group (OCG), to one logicalchannel. As shown in Table 1-4(a), each logical channel is configuredwith an OCG. For example, {sCellIndex#2, sCellIndex#i, sCellIndex#m} isthe OCG for LCH#a, and {sCellIndex#3, sCellIndex#j } is the OCG forLCH#b. After receiving an OCG, the MAC entities of the transmitter sidemay take the duplicated PDCP PDU packets from one logical channel anddeliver the PDCP PDU packets to the one or more cells in the OCG. Insome other implementations, the sCellIndex in Table 1-4(a) may bereplaced by ServCellIndex, as shown in Table 1-4(b).

TABLE 1-4(a) LCH configured with an OCG (indicated by sCellIndex) TypeLCH <-> Operation Cell Group Duplication LCH#a sCellIndex#2 sCellIndex#isCellIndex#m LCH#b sCellIndex#3 sCellIndex#j N.A.

TABLE 1-4(b) LCH configured with an OCG (indicated by ServCellIndex)Type LCH <-> Operation Cell Group Duplication LCH#a ServCellIndex#2ServCellIndex#i ServCellIndex#m (=sCellIndex#2) (=sCellIndex#i)(=sCellIndex#m) LCH#b ServCellIndex#3 ServCellIndex ServCellIndex#0(=sCellIndex#3) (=sCellIndex#j) (=‘0000’ (PCell))

In some implementations, base station 204 may configure and provide anOCG to UE 202, according to the Base Station Explicit Signalingapproach, in the mapping configuration in action 210, and indicate whichoperation cell(s) in the OCG to use after the Activation of Duplicationmessage. Thus, after receiving the Activation of Duplication message inaction 220, UE 202 may transmit the pending packets in one logicalchannel by referring to the configured OCG each time UE 202 obtains a ULgrant from each serving Cell. In some other implementations, in theActivation of Duplication message, base station 204 may use additionaloperation cell bits, where the details of operation cell bits are shownin Table 1-5, to implicitly indicate which operation cells can beutilized by UE 202 for Duplication.

As shown in Table 1-5, the cells in the OCG may be indexed based ontheir sequences in the OCG (e.g., in Table 1-5, sCellIndex#2 is thefirst cell; sCellIndex#i is the second cell; sCellIndex#m is the thirdcell). UE 202 may learn the indices and the corresponding cells in theOCG from the mapping configuration. Then, based on the indices for thecells, the operation cell bits may be provided in the Activation ofDuplication message by base station 204 to UE 202, to indicate whichcell(s) that UE 202 is allowed to use as operation cell(s).

TABLE 1-5 Operation cell bits provided to indicate which operation cellsmay be utilized by a UE based on the indices of operations cells in theOCG Operation Cell bits in Activation of Duplication message Cell in OCG00 sCellIndex#2 01 sCellIndex#i 10 sCellIndex#m

In some implementations, base station 204 may provide a mappingconfiguration, between the logical channels and operation cellsexplicitly, to UE 202. UE 202 may re-select the operation cell(s) basedon pre-defined triggering events. UE 202 may select at least oneoperation cell from the OCG to deliver the duplicated packets. When apre-defined triggering event occurs, UE 202 may re-select anotheroperation cell in the same OCG to continue delivering the duplicatedpackets substantially without interruption.

It should be noted that in various implementations of the presentdisclosure, in each mapping configuration for Duplication, an operationcell may not be configured to more than one OCG to prevent the pendingpackets of different logical channels from being delivered on the samecomponent carrier.

In one implementation, base station 204 may indicate the Duplicationfunction of at least one radio bearer (e.g., DRB(s)) is activated bydelivering the Activation of Duplication message to UE 202. Then, toeach logical channel in which duplication is be activated, base station204 may further configure the operation cell(s) by providing theoperation cell bits for each logical channel in the Activation ofDuplication message.

In Table 1-6, in an example Activation of Duplication message, basestation 204 (e.g., a gNB) indicates which radio bearer(s) shouldactivate the Duplication function in the PDCP layer and what logicalchannels that duplicated packets are delivering in RLC layer.

TABLE 1-6 Example Activation of Duplication message. Format ContentActivation Bearer DRB ID/SRB ID Operation Cell of 1^(st) LCH 01Operation Cell of 2^(nd) LCH 10

Under the MC PDCP PDU Duplication operation, in one implementation, amaster node (MN) may provide a mapping configuration to a UE, where themapping configuration includes mapping rules between the logicalchannels and operation cells of the MCG and/or SCGs. Before the MNdelivers the mapping configuration to the UE, the MN may coordinate withone or more secondary nodes (SNs) through backhaul, where the SNs mayeach provide their operation cells or OCG for Duplication. The MN maythen forward the mapping configuration between the UE and the SNs.

For the MC PDCP PDU Duplication operation, in one implementation, UE 202may be configured with a MCG and two or more SCGs (e.g., MCG 110, SCG120, and SCG 130 in FIG. 1), where a master node is in charge of thePCell and SCell(s) in the MCG, a secondary node is in charge of thePSCell and SCell(s) in first SCG (e.g., SCG#1), and another secondarynode is in charge of the PSCell and SCell(s) in the second SCG (e.g.,SCG#2).

FIG. 3A is a diagram illustrating a master node providing a mappingconfiguration for Duplication to a UE, where the mapping configurationincludes mapping rules for MCG and SCGs, in accordance with one exampleimplementation of the present disclosure. As illustrated in diagram300A, in action 332, MN 304 may send a Configuration for Duplicationrequest to SN 306 for operation cell(s) or OCG for Duplication from SN306. In action 334, SN 306 may provide its operation cell(s) or OCG forDuplication to MN 304. In action 336, MN 304 may send a Configurationfor Duplication request to SN 308 for operation cell(s) or OCG forDuplication from SN 308. In action 338, SN 308 may provide its operationcell(s) or OCG for Duplication to MN 304. In action 340, MN 304 mayprovide a mapping configuration for Duplication to UE 302, where themapping configuration includes mapping rules between the logicalchannels and operation cells (or OCGs) of all of the MCG and SCGs fromMN 304, SN 306, and SN 308.

In action 350, UE 302 may activate Duplication after receiving anActivation of Duplication message from MN 304, for example. In someimplementations, the RAN may not immediately activate Duplication afterdelivering the Activation of Duplication message to UE 302.

In action 360, UE 302 may stop applying one or more of the allowedserving cells to the one or more logical channels when receiving aDeactivation for Duplication message (or a deactivation message ofpacket duplication).

Table 2-1(a) shows an example mapping configuration format forDuplication in action 340, when MN 340 provides the mappingconfiguration to UE 302. The mapping configuration includes mappingrules between the logical channels and operation cells of all of the MCGand SCGs.

TABLE 2-1(a) MN providing CG indices and SCellindices in a mappingconfiguration LCH <-> Operation Cell in MC scenario Type CG index LCHCell index DL Duplication MCG index LCH#a sCellIndex#1 SCG#1 index LCH#bsCellIndex#2 SCG#2 index LCH#c sCellIndex#3 UL Duplication MCG indexLCH#m “0000”(PCell) SCG#1 index LCH#n sCellIndex#1

As shown in Table 2-1(a), MN 304 may provide different mappingconfigurations for DL Duplication and UL Duplication across differentcell groups. In addition, MN 304 may provide cell group (CG) indices toMCG, SCG#1, SCG#2 (e.g., {MCG index, SCG#1 index, SCG#2 index}), so UE304 may identify the cell groups based on the CG indices in Table2-1(a). The RAN may provide the CG indices to UE 302 through RRCsignaling before MN 304 providing the mapping configuration to UE 302.In some implementations, default cell(s) (e.g., PCell in MCG or PSCellin SCG) may be configured in technical specifications or by the servingbase station (e.g., a gNB) for Duplication. In such cases, the RAN mayonly provide indication of the remaining cells for Duplication.Otherwise, the RAN may also need to provide indication of PCell in MCGand/or PSCell in SCG in the mapping configuration, as shown in Table2-1(a).

In some implementations, the format for mapping configuration forDuplication in action 340 may be provided through the proposedServCellIndex, as shown in Table 2-1(b).

TABLE 2-1(b) MN providing ServCellIndices in a mapping configuration LCH<-> Operation Cell in MC scenario for DRB#0 Radio Bearer CG index LCHCell index DRB ID#0 MCG index LCH#a ServCellIndex#1 (=sCellIndex#1)SCG#1 index LCH#b ServCellIndex#2 (=sCellIndex#2) SCG#2 index LCH#cServCellIndex#0 (=“0000”(PSCell))

In some implementations, PCell and/or PSCell may be the default cells todeliver duplicated PDCP packets. Thus, UE 302 may only need to know theSCG indices for Duplication. As shown in Table 2-2, MN 304 may providethe CG indices which are involved in the DL and/or UL Duplicationoperations, and UE 302 may know which PCell and/or PSCell of theinvolved CGs are to be utilized for Duplication.

TABLE 2-2 MN only providing CG indices in a mapping configuration. TypeLCH <-> Selected CG (PCell/PSCell is the default cell) DL DuplicationMCG index LCH#a SCG index#1 LCH#b UL Duplication MCG index LCH#m SCG#1index LCH#n SCG#2 index LCH#l

Under the MC PDCP PDU Duplication operation, in one implementation, theRAN may provide multiple candidates across multiple CGs. As shown inTable 2-3, the RAN may configure multiple mapping rules between logicalchannels and operation cells for MC PDCP PDU Duplication. In theimplementation shown in Table 2-3, a UE may only select a number oflogical channels (and the corresponding cells) for Duplication. Forexample, in Table 2-3, three logical channels and the correspondingcells are configured in the candidate lists for UL Duplication. Withreference to FIG. 3A, MN 304 may determine and/or configure the numberof logical channels that UE 302 is allowed to select from the list. Forexample, UE 302 may select any two of the three logical channels (e.g.,LCH#a, LCH#b, and LCH#c in Table 2-3) and the corresponding cells (e.g.,sCellIndex#1 of MCG, sCellIndex#2 of SCG#1, and sCellIndex#3 of SCG#2 inTable 2-3) or an OCG listed in Table 2-4. In some implementations, thenumber of duplicated logical channels may have a default value specifiedin technical specification.

TABLE 2-3 Multiple candidates across multiple CGs in the MC PDCP PDUDuplication operation LCH <-> Operation Cell in MC scenario Type CGindex LCH Cell index UL Duplication MCG index LCH#a sCelllndex#1 SCG#1index LCH#b sCellIndex#2 SCG#2 index LCH#c sCelllndex#3 Number ofduplicated logical channel 2

In some implementations, an OCG may be represented by a CG index (e.g.,an MCG index or an SCG index), which means that all of the cells in theCG are included in the OCG. As shown in Table 2-4, a MCG index may beprovided to LCH#m, which means that the OCG of LCH#m covers the PCelland SCells of the MCG. An SCG#1 index may be provided to LCH#n, whichmeans that the OCG of LCH#n covers the PSCell and SCells of the SCG#1.An SCG#2 index may be provided to LCH#1, which means that the OCG ofLCH#1 covers the PSCell and SCells of the SCG#2.

TABLE 2-4 The OCG of each LCH being provided through a CG index. TypeLCH <-> OCG UL Duplication LCH#m MCG index LCH#n SCG#1 index LCH#l SCG#2index

In some implementations, MN 304 may provide or indicate the allowedoperation cell(s) of the logical channels in the Activation ofDuplication message (e.g., as referred to in Table 1-6). In someimplementations, MN 304 may provide or indicate the allowed operationcell(s) by providing the CG index(ices) and/or cell index(ices) in theActivation of Duplication message. The RAN may provide the CG index ofeach corresponding CG to UE 302 through dedicated signaling (e.g., RRCsignaling), as shown in Table 2-5.

TABLE 2-5 RAN providing the CG index of each CG to a UE throughdedicated signaling. Configured CG to a UE CG index MCG 00 1^(st) SCG 012^(nd) SCG 10

Under the MC PDCP PDU Duplication operation, in another implementation,an MN and two or more SNs may each directly provide a mappingconfiguration for Duplication to a UE for the corresponding MCG andSCGs.

FIG. 3B is a diagram illustrating a master node and two or moresecondary nodes each providing a mapping configuration for Duplicationto a UE, in accordance with one example implementation of the presentdisclosure. As illustrated in diagram 300B, in action 331, MN 304 maysend a message to SN 306 (e.g., a request for Configuration forDuplication in SCG#1), through a backhaul connection, to request SN 306to provide a mapping configuration for Duplication in SCG#1 to UE 302.In action 333, MN 304 may send a message (e.g., a request forConfiguration for Duplication in SCG#2) to SN 308, through a backhaulconnection, to request SN 308 to provide a mapping configuration forDuplication in SCG#2 to UE 302. In action 335, MN 304 may configure theoperation cells (e.g., PCell and/or SCell(s)) in the MCG, and providethe mapping configuration for Duplication in the MCG to UE 302. Inaction 337, SN 306 may configure the operation cells (e.g., PSCelland/or SCell(s)) in SCG#1, and provide the mapping configuration forDuplication in SCG#1 to UE 302. In action 339, SN 308 may configure theoperation cells (e.g., PSCell and/or SCell(s)) in SCG#2, and provide themapping configuration for Duplication in SCG#2 to UE 302. In action 350,UE 302 may activate Duplication after receiving an Activation ofDuplication message from MN 304, for example. In some implementations,the RAN may not immediately activate Duplication after delivering theActivation of Duplication message to UE 302. In action 360, UE 302 maystop applying one or more of the allowed serving cells to the one ormore logical channels when receiving a Deactivation for Duplicationmessage (or a deactivation message of packet duplication).

In the present implementation, since MN 304, SN 306 and SN 308 may eachprovide a mapping configuration by themselves, the format of eachmapping configuration for Duplication may follow those described withrespect to the CA PDCP PDU Duplication operation, as shown in Table 1-1through Table 1-4(b).

In some implementations, UE 302 may select logical channels and thecorresponding operation cells for Duplication. For the multiplecandidates across multiple CGs configuration, all the mappingconfigurations from multiple CGs for Duplication are combined as one OCGto UE 302. In addition, the number of duplicated logical channels forDuplication may be configured to UE 302 explicitly (e.g., throughexplicit signaling) or implicitly (e.g., by a default value in technicalspecification). Based on the list of configured candidates acrossmultiple CGs, UE 302 may select a certain number of allowed logicalchannels and the corresponding operation cells for Duplication. In someimplementations, UE 302 may re-select another logical channel(s) and thecorresponding operation cell(s) from the list of allowed logicalchannels and the corresponding operation cells to deliver the duplicatedPDCP PDU packets based on one or more pre-defined triggering events,which are described with reference to the Event-based UESelf-(re)selection approaches herein.

Under the MC PDCP PDU Duplication operation, in another implementation,an MN and two or more SNs may each directly provide a mappingconfiguration for Duplication to a UE for the corresponding MCG andSCGs.

FIG. 3C is a diagram illustrating a master node and two or moresecondary nodes each providing an operation cell indication forDuplication to a UE, in accordance with one example implementation ofthe present disclosure.

As illustrated in diagram 300C, actions 331, 333, 335, 337, and 339 maybe substantially similar to actions 331, 333, 335, 337, and 339,respectively, in FIG. 3B. In FIG. 3C, the RAN (e.g., having MN 304, SN306, and SN 308) may further indicate the operation cell(s) throughdedicated signaling (e.g., MAC CEs). In some implementations, MN 304, SN306, and SN 308 may each indicate their operation cell(s) of the logicalchannel(s) in their respective Activation of Duplication messages (e.g.,as shown in Table 1-6). As shown in diagram 300C, during Duplication350, in action 351, in an Activation of Duplication message, MN 304 mayprovide an indication of allowed operation cell(s) (e.g., PCell andSCell(s)) in MCG to UE 302. In action 353, in an Activation ofDuplication message, SN 306 may provide an indication of allowedoperation cell(s) (e.g., PSCell and SCell(s)) in SCG#1 to UE 302. Inaction 355, in an Activation of Duplication message, SN 308 may providean indication of allowed operation cell(s) (e.g., PSCell and SCell(s))in SCG#2 to UE 302. In some other implementations, the operation cell(s)corresponding to one LCH may be indicated by CG index(ices) and/or cellindex(ices). In action 360, UE 302 may stop applying one or more of theallowed serving cells to the one or more logical channels when receivinga Deactivation for Duplication message (or a deactivation message ofpacket duplication).

As discussed above, in various implementations of the presentdisclosure, the Base Station Explicit Signaling approach, the UESelf-(re)selection approach, or a hybrid combination of both may beapplicable to Duplication. In addition, a base station (e.g., gNB) mayconfigure and/or determine which of these approaches is suitable forDuplication for the UE.

In Table 3, three examples are provided showing in mappingconfigurations for Duplication that a base station may provide to a UE.

TABLE 3 Mapping Configurations for Duplication Event MappingConfiguration for Duplication Implementation#X Base Station ExplicitSignaling approach only. Base station (e.g., gNB) may indicate whichcells/CCs are the operation cell(s) for Duplication after theDuplication is activated. Implementation#X2 (1) RAN may activateDuplication without indicating the operation cells to UE. (2)Event-based UE Self-(re)selection approach only. UE may (re)selectoperation cell(s) when at least one triggering event is fulfilled. (3)RAN may provide candidate cells for UE to select the Operation Cells andso UE may select the operation cell(s) from the group of candidatecells. Implementation#X3 (1) Base Station Explicit Signaling approachonly, by default. UE may implement Duplication based on the mappingconfiguration provided by gNB. (2) Triggering events for the UESelf-(re)selection approach are also provided. UE may apply the UESelf-(re)selection approach when at least one triggering event isfulfilled. (3) RAN may provide candidate cells for UE to select theoperation cell(s).

In Implementation#X1, an MN may provide the mapping configuration to theUE through the Base Station Explicit Signaling approach based on the CAPDCP PDU Duplication operation and the MC PDCP PDU Duplicationoperation. In Implementation#X2, an MN may indicate the Event-based UESelf-(re)selection approach, an example of a hybrid combination of theBase Station Explicit Signaling approach and the UE Self-(re)selectionapproach, to the UE for UL Duplication, for example. In the Event-basedUE Self-(re)selection approach, one or more pre-defined triggeringevents are provided to the UE through the mapping configuration. Then,the UE may choose the mapped cells by itself when at least onetriggering event is fulfilled. In Implementation#X3, both the BaseStation Explicit Signaling approach and the UE Self-(re)selectionapproach are configured to the UE. The UE may apply the Base StationExplicit Signaling approach by default after receiving the mappingconfiguration from the RAN. In some implementations, the MN mayconfigure an OCG for the UE to choose among the operation cell(s) in theconfigured OCG for Duplication. Also, the triggering event(s) of theEvent-based UE Self-(re)selection approach may be decided by eachlogical channel and/or each operation cell. As such, the re-selection ofeach operation cell may be implemented independently.

FIG. 4 is a diagram showing Implementation#X3 according to animplementation of the present disclosure. As illustrated in diagram 400,in action 410, base station 404 (e.g., gNB) may configure the options(e.g., the Base Station Explicit Signaling approach (as default) and theEvent-based UE Self-(re)selection approach) in the mapping configurationfor Duplication, and send the mapping configuration for Duplication toUE 402. In action 420, UE 402 may determine or identify the operationcell(s) based on the Base Station Explicit Signaling approach. In action430, at least one triggering event of at least one operation cell isfulfilled. In action 440, UE 402 may (re)select another operation cellto replace the operation cell(s).

The Event-based UE Self-(re)selection approach is discussed in detailbelow. Also, different options may be applied to DL Duplication and ULDuplication independently (e.g., the Base Station Explicit Signalingapproach may be applied to DL Duplication, while the UESelf-(re)selection approach may be applied to UL Duplication). Also, insome implementations, the RAN may indicate operation cell(s) through theBase Station Explicit Signaling approach periodically. In addition, theperiodicity that the RAN delivers the operation cell(s) may also beconfigured and provided to the UE, so that the UE may know when toreceive and update the operation cell(s) for Duplication based on theperiodicity.

With reference to FIG. 4, base station 404 (e.g., serving MN and/or SNs)may provide triggering events to UE 402 in the mapping configuration forDuplication, where the triggering events may activate UESelf-(re)selection of operation cell(s) in the Event-based UESelf-(re)selection approach. Table 4-1 includes some of the exampletriggering events according to some implementations of the presentdisclosure.

TABLE 4-1 Example implementations of the triggering events forevent-based UE self- (re)selection Triggering event for UESelf-(re)selection UE's Behavior Event#Y1 The signaling quality of oneCell (e.g., (1) UE stops delivering Cell#Yl1 of UL Duplication is worsethan duplicated PDCP PDUs on a pre-defined threshold (a.k.a. T_(Y1)).Cell#Y1 and then re-selects another available cell by itself. Event#Y1-AThe Number of NACK response to UE on (1) UE stops delivering one Cell(e.g., Cell#Y1) within the duplicated PDCP PDUs on moving time window(time span= Cell#Y1 and then re-selects P_(NACK) _(—) _(1A)) is largerthan N_(NACK-1A). another available cell by itself. Event#Y2 The amountof pending packets in one (1) UE stops delivering packets logicalchannel (e.g., LC#Y2) is higher on Cell#Y2 and re-selects than apre-defined threshold (T_(Y2)). another available cell by itself. (Note:LC#Y2 is correspondent to Cell#Y2) Event#Y3 One configured cell (e.g.,Cell#Y3) is (1) UE stops delivering de-activated and RAN does notconfigure duplicated packets on another cell for the UE to deliverCell#Y3. duplicated PDCP PDUs. (2) UE replaces Cell#Y3 to the PCell (ifCell#Y3 is in MCG) or PSCell (if Cell#Y3 is in an SCG) for ULDuplication (and PCell/PScell would not be de-activated in the presentimplementations). Event#Y4 Link problem (e.g., Radio link failure) of(1) UE stops delivering the PSCell of the SCG, which is at leastduplicated packets on the one Cell is configured for UL SCG Duplication.(2) Then, UE is to re-select another available CG, split radio bearer,and the corresponding Operation Cell, by itself.

As shown in Table 4-1, Event#Y1 is related to the channel quality (e.g.,the RSRP (Reference Signal Receiving Power) or RSRQ (Reference SignalReceiving Quality) or RSSI (Received Signal Strength Indicator) value,which the UE obtains by measuring the reference signals delivered by theserving cell corresponding to the component carrier) of the operationcell(s). With regard to Event#Y1, while the UE is delivering duplicatedPDCP packets in Cell#Y1, the UE may detect that the signaling quality ofCell#Y1 is worse than a pre-defined threshold (e.g., T_(Y1)). WhenEvent#Y1 is fulfilled, the UE may stop delivering the duplicated PDCPpackets on Cell#Y1. Instead, the UE may re-select another operation cellautomatically for UL Duplication, for example.

Event#Y1-A (NACK Response on the Operation Cell):

As shown in Table 4-1, Event#Y1-A is related to a NACK response on theoperation cell. With regard to Event#Y1-A, while the UE is deliveringduplicated PDCP packets in Cell#Y1, the UE may detect or observe anacknowledgement/non-acknowledgement (ACK/NACK) response (e.g., a hybridautomatic repeat request response (HARQ) ACK/NACK) from the RAN forprevious UL packet deliveries. For example, the number of NACK responsesfrom the RAN in one operation cell may be regarded as an indicator forthe UE to trigger operation cell reselection. In Event#Y1-A, the RAN mayfurther indicate the {N_(NACK 1A), P_(NACK 1A)} to the UE. The UE maymonitor the ACK/NACK responses of UL packets delivered on the operationcell(s). The UE may set a moving time window, where the timespan=P_(NACK_1A), in time domain (e.g., 100 ms or 50 subframes). Themoving time window is moved forward in time domain with the advance ofUL packet delivering on the operation cell. Then, Event#Y1-A may betriggered when the UE notices the total number of NACK responses in themoving time window is larger than N_(NACK_1A). When Event#Y1-A isfulfilled, the UE may stop delivering packets on Cell#Y1 and (re)selectanother operation cell.

As shown in Table 4-1, Event#Y2 is related to the buffer status of thelogical channel. With regard to Event#Y2, the UE is deliveringduplicated PDCP packets in Cell#Y2, where Cell#Y2 may be decided by theBase Station Explicit Signaling and/or the Event-based UESelf-(re)selection approach, and one logical channel (e.g., LC#Y2) isconfigured to map to Cell#Y2 for UL Duplication. In Event#Y2, thetriggering event is the amount of pending packets in LC#Y2 is higherthan a pre-defined threshold (e.g., T_(Y2)). When Event#Y2 is fulfilled,the UE may stop delivering packets on Cell#Y2 and (re)select anotheroperation cell.

As shown in Table 4-1, Event#Y3 is related to deactivation by the RAN.With regard to Event#Y3, the UE is delivering duplicated PDCP packets inCell#Y3, where Cell#Y3 may be decided by the Base Station ExplicitSignaling and/or the Event-based UE Self-(re)selection approach. InEvent#Y3, the triggering event is that Cell#Y3 is de-activated, and theRAN does not configure another cell for the UE to deliver the duplicatedPDCP PDU packets. In this situation, the UE may stop delivering theduplicated packets on Cell#Y3, and decide a new operation cell by itselfbecause the RAN does not configure a new operation cell for the UE.

As shown in Table 4-1, Event#Y4 is related to a radio link problem(e.g., failure) of a PSCell of an SCG. With regard to Event#Y4, one RLCbearer in SCG (e.g., SCG#1 and one corresponding RLC bearer SCell#k inSCG#1) may be configured for Duplication. Then, Event#Y4 is fulfilledwhen the radio link of the PSCell in SCG#1 fails. When Event#Y4 occurs,SCell#k may also be terminated by the radio link problem of the PSCellof SCG#1. Thus, the UE may need to move the duplicated packets, whichare going to be dispatched to the SCG, to another CG. In this condition,the UE may need to decide the corresponding CG, RLC bearer, and thecorresponding operation cell(s) on its own.

TABLE 4-2 Example thresholds for Event-based UE Self-(re)selectionThreshold Definition Unit T_(Y1) Threshold for DL link signal dB or dBmquality (e g., RSRP, RSRQ, RSSI) T_(Y2) Threshold of the amount ofByte(s) data pending in the logical channel P_(NACK) _(—) _(1A) Timespan of the moving Subframe(s) or time window in Event#Y1-Amillisecond(s) N_(NACK) _(—) _(1A) Threshold for the Integer valueaccumulated number of NACK responses in the moving time window inEvent#Y1-A

Table 4-3 shows example operation cell criteria for a UE to (re)select anew operation cell (e.g., to replace the “original” operation cell).

TABLE 4-3 Example operation cell (re)selection criteria for UE OperationCell Selection (Re-selection) Criteria for UE Level#1 C#1-1 UE selectsthe same CG with original Operation Cell CG C#1-2 UE selects differentCG with original Operation Cell C#1-3 Default CG (e.g., MCG) C#1-4 UEautonomous selection Level#2 C#2-1 UE decides based on signal strength(e.g., RSRP, RSRQ, Cell RSSI) among cells. C#2-2 UE decides based onchannel occupancy ratio of shared radio resource by UEs among CellsC#2-3 UE decides based on the buffer status of logical channel C#2-4Default Cell (e.g., PCell in MCG/PSCell(s) in SCG(s)) C#2-5 UEautonomous selection

The selection process may be divided into two levels, where the firstlevel may be CG level (Level#1 selection), and the second level may becell level (Level#2 selection).

In Level#1 selection, the RAN may configure the UE to select a newoperation cell on the same CG as the original operation cell (C#1-1). Inone implementation, the RAN may configure a default CG (e.g., MCG) forthe UE to re-select the new operation cell (C#1-3). In anotherimplementation, the RAN may configure the UE to select a new operationcell on another CG (C#1-2), which is different than the CG of theoriginal operation cell. In another implementation, the UE maydecide/determine to select a CG by itself (C#1-4).

In Level#2 selection, the UE may decide a new operation cell based on:(1) received signal strength (e.g., RSRP, RSRQ, RSSI) of the cells(e.g., C#2-1) on the UE side; (2) channel occupancy ratio of sharedradio resource in the cells (e.g., C#2-2). In some implementations, theUE estimates the channel occupancy ratio of one operation cell byevaluating the radio resource (e.g., Physical Resource Blocks) sharedamong UEs in the operation cell to transmit uplink packets (e.g.,duplicate packets in uplink). The UE is to monitor the received signalstrength of these shared PRBs, where one PRB is regarded as occupied ifthe received signal strength on the PRB is higher than (or equal to) apre-defined threshold of signal strength (in dB or dBm). By contrast,one PRB is regarded as un-occupied if the received signal strength onthe PRB is not higher than the pre-defined threshold. The UE is toevaluate the channel occupancy ratio of one operation cell bycalculating the number of occupied PRBs in the shared PRBs over thetotal number of shared PRBs. Then, the UE is to decide to re-select theoperation cell if the channel occupancy ratio of the shared PRB in oneoperation cell is higher than a pre-defined channel occupancy ratiothreshold, wherein the channel occupancy ratio threshold is a fractionbetween 0 and 1; (3) buffering status of the logical channels associatedwith the cells (e.g., C#2-3). In some implementations, a default cell(e.g., PCell in MCG/PSCell(s) in SCG(s)) may be configured for the UE toselect a new operation cell (e.g., C#2-4). It is also possible that theUE may select a new operation cell by considering any combination ofC#2-1 through C#2-4. Also, in some implementations, the UE may select anew operation cell based on its own autonomous selection (e.g., C#2-5).

In some implementations, the RAN may limit the candidate CGs/Cells tothe UE when UE Self-(re)selection is configured with Base StationExplicit Signaling. Based on the CA and MC PDCP PDU Duplicationoperations, the UE may select the operation cell(s) based on a given OCGor given multiple candidates across multiple CGs.

In some implementations, the RAN may send feedback responses to instructthe UE to re-select an operation cell for Duplication. In someimplementations, the serving base station may not configure any mappingfor Duplication, such that the UE may need to select the appropriatecells for duplicated packets transmission (here the appropriate oneshall also take the constraint that same packets may not be put into theuplink grants of the same Cell for packet transmissions). When theserving base station receives the duplicated PDCP PDU packets, theserving base station may evaluate and determine whether reliabilityrequirement of the radio bearer (DRB or SRB) is achieved. If suchself-selection/mapping does not meet the target (e.g., target blockerror rate), the serving base station may send a feedback response to UEto change the current selection/mapping. The RAN feedback response maybe accomplished by transmitting an RRC message or MAC Control Element(CE), or by a PDCP control PDU. It is also noted the indication is on aper-radio bearer basis such that the serving base station may reflectthe un-satisfied situations to each DRB/SRB separately. When the UEreceives the indications, the UE may change the path for Duplication. Inaddition, if the serving base station identifies reliability requirement(of the corresponding radio bearer) is still not fulfilled after sendingthe feedback response to the UE, the serving base station mayde-activate (or de-configure) Duplication and then seek other possiblesolutions (e.g., using Repetition of TBs in the physical layer) toimprove quality of service of the radio bearer.

CASE 2: Activation/Deactivation of PCell, PSCell, and SCells

For the purpose of power saving, in LTE systems, a base station (e.g.,an eNB) may instruct a UE to de-activate SCell(s) after the UE isconfigured with SCell(s) in CA and DC operations. The UE does not needto perform the following actions on a de-activated SCell: (i) deliveringsounding reference signal(s); (ii) providing measurement reports (e.g.,Channel quality Indicator (CQI), Precoding Matrix Indicator (PMI), RankIndicator (RI)) about the de-activated SCell; (iii) blind decoding ofcontrol channels of the de-activated SCell or data reception.

In the LTE systems, there are several ways for a UE to activate anddeactivate the SCell(s). For example, a base station may instruct the UEto activate or deactivate the SCell(s) using a MAC CE. In anotherexample, a base station may configure a Deactivation Timer(sCellDeactivationTimer) to the UE. The UE may set a Deactivation Timerto each SCell. The UE may set the Deactivation Timer of each SCell toequal to sCellDeactivationTimer after the corresponding SCell isactivated. During packet exchange, the UE may restart the DeactivationTimer=sCellDeactivationTimer every time after the UE obtains a UL grantor a DL assignment for the activated SCell. Otherwise, the UE mayde-activate the SCell automatically after the De-activation Timer of thecorresponding SCell expires. In some implementations, the UE mayconsider sCellDeactivationTimer=infinity if the RAN does not configurean sCellDeactivationTimer to the UE. Also, when ansCellDeactivationTimer is configured to a UE, the RAN may also startcounting a Deactivation Timer of each SCell to the UE. Then, the RAN mayconsider an SCell is de-activated if the Deactivation Timer of the SCellexpires. As such, the RAN would not provide control signaling to the UEon the deactivated SCell. In yet another example, all SCells may bedeactivated by default, if the UE receives an RRC Reconfigurationmessage which contains mobilityControlinfo (e.g., when the serving basestation triggers a handover to the UE) from the serving base station.However, it is noted that, in LTE systems, both PCell and PSCell cannotbe deactivated, although it is possible to deactivate SCell(s) in anSCG.

In various implementations of the present disclosure, Duplication may beaffected by a Deactivation Timer. In addition, a PSCell may bedeactivated when a PSCellDeactivationTimer is applied to a PSCell. Insome implementations, a PSCell may be deactivated if all of the SCellsin the CG are deactivated, and the RAN (e.g., MN or SN) may configure aPSCellDeactivationTimer to a UE. In some implementations, both a UE andan SN of the CG may set a deactivation timerPSCell=PSCellDeactivationTimer, and start counting if all of the SCellsto the UE are deactivated. In some implementations, the deactivationtimer PSCell may be reset if a new packet exchange on a PSCell or anySCell in the CG is activated by the RAN. In some implementations, theRAN can configure independent PSCellDeactivationTimers to differentPSCells of different CGs of a UE.

For brevity, the following implementations of the deactivation timer aredescribed with respect to SCells (e.g., SCellDeactivationTimer and theDeactivation Timer for SCells). However, implementations of thedeactivation timer may also be applied to both PCell and PSCell.

In various implementations of the present disclosure, a DeactivationTimer may be disabled either explicitly or implicitly.

Table 5-1 illustrates example implicit approaches to disable aDeactivation Timer.

TABLE 5-1 Example implicit approaches to disable a Deactivation TimerImplicit approaches to disable a De-activation Timer Approach#Z-1 UEdisables the De-activation Timers of all SCells in all CGs when (AllCGs) Duplication is activated (or configured) by RAN UE may re-setDe-activation Timer of all SCells in all CGs = SCellDeactivationTimerand then start counting after Duplication is de-activated (orde-configured) by RAN. Approach#Z-2 UE disables the De-activation Timersof all SCells of the CG which (CG based) involves Duplication (at leastone Cell in the CG is the Operation Cell). UE may re-set De-activationTimer = SCellDeactivationTimer to all SCells in the CG and then startcounting when no Cell in the CG is involved in Duplication (OperationCells are re-selected by Base Station Explicit Signaling or Event-basedUE Self-(re)selection). Approach#Z-3 UE may only disable theDe-activation Timers of SCells which are (SCell based) Operation Cells(e.g., selected by Implementation#X1 or Implementation#X2). UE mayre-set De-activation Timer of the SCell = SCellDeactivationTimer whenthe SCell is not an Operation Cell (e.g., re-selected by Base StationExplicit Signaling or Event-based UE Self-(re)selection). Approach#Z-4(1) All the counting of De-activation Timers are un-changed. (minimumnumber (2) RAN defines the “minimum number of activated Cell” (N_(A)) toof activated Cell) the UE. (3) UE is to de-activate SCells until numberthe activated Cells = N_(A) Steps (1)-(3) may be applied to all theSCells or it can be implemented per CG basis. The PCell/PSCell may ormay not be included in the counting of number of activated Cell.

In some implementations, a UE may disable the Deactivation Timers of allSCells in all CGs when Duplication is activated (Approach#Z-1). In someimplementations, a UE may disable the Deactivation Timers of all SCellsin one CG (Approach#Z-2) when at least one Cell in the CG is selectedfor Duplication. In some implementations, A UE may disable theDeactivation Timer of the SCell selected for Duplication (Approach#Z-3).In Approach#Z-4, the counting process of the Deactivation Timers are thesame. However, the RAN may provide a “minimum number of activated Cell(N_(A))” to the UE to prevent the UE from deactivating too many cells toavoid not having enough cells for Duplication. The UE may deactivate theSCells based on the Deactivation Timers until the number of activatedcells reaches to the N_(A). When the number of activated cells reachesto the N_(A) during Duplication, the UE may disable the DeactivationTimers of all SCells until the number of activated cells becomes greaterthan the N_(A).

It is noted that in the LTE DC operation, an sCellDeactivationTimer isprovided for each CG, and the value of the sCellDeactivationTimer isapplied to all of the SCells in the CG. By contrast, accordingimplementations of the present disclosure, the RAN may configuredifferent sCellDeactivationTimer values to different cells and theircorresponding component carriers.

In addition to implicit approaches to disable a Deactivation Timer,implementations of the present disclosure may also disable theDeactivation Timer through explicit approaches. For example, the RAN(e.g., having MN and SN(s)) may configure two values to ansCellDeactivationTimer, one is sCellDeactivationTimer(Duplication_activated) and the other isCellDeactivationTimer(Duplication_de-activated), when the RAN isconfiguring Duplication to the UE. So, the UE may set DeactivationTimer=sCellDeactivationTimer(Duplication_activated) after Duplication isactivated. On the other hand, the UE may set the DeactivationTimer=sCellDeactivationTimer(Duplication_de-activated) when Duplicationis de-activated. The sCellDeactivationTimer (activated) andsCellDeactivationTimer(de-activated) may be configured by the RAN (e.g.,MN or SN). In some implementations, the RAN may only providesCellDeactivationTimer (activated) or sCellDeactivationTimer(de-activated) to the UE. In some implementations, the RAN may configurea set of {sCellDeactivationTimer (activated) and/orsCellDeactivationTimer(de-activated)} to all SCells (and PSCells) of theUE. In some other implementations, the RAN may configure different{sCellDeactivationTimer (activated) and/orsCellDeactivationTimer(de-activated)} to each component carrier, CG, orcell.

In some implementations, the deactivation of a cell may be independentof Duplication operations, where the UE may decide and/or select theappropriate cells to activate and deactivate Duplication. For CAoperations, if all SCells are deactivated, then the Duplication on theSCells may be deactivated accordingly. From the UE/RAN's perspective, ifthere is no available SCell for Duplication, the UE/RAN may stop theactivated Duplication functionalities in the PDCP layer accordingly.Then, the serving base station (e.g., a gNB) may need to identify othersolutions to meet the service reliability.

In some implementations, when event-based UE self-(re)selection isconfigured, a UE may (re)select an operation cell(s) automatically, andmay need to report the selected operation cell(s) for Duplication (e.g.,UL Duplication), if the Deactivation Timer of the selected operationcell(s) (or CG) needs to be disabled during Duplication, and/or beenabled after Duplication is deactivated. This is because the basestation (e.g., gNB) may consider that an SCell is deactivatedautomatically if the base station has configured sCellDeactivationTimerto the UE, but the UE decides to utilize the deactivated SCell forDuplication based on event-based UE self-(re)selection and theDeactivation Timer is disabled. In this situation, the UE attempts todeliver packets on an SCell which the base station deems to bedeactivated. To avoid conflict between the UE and the serving basestation, the UE needs to inform the RAN which SCell(s) the UE choosesfor Duplication after the UE decides to select/re-select the operationcell(s) through the event-based UE self-(re)selection.

FIG. 5A is a diagram showing a method of a UE informing operationcell(s) for Duplication to various network nodes, in accordance with animplementation of the present disclosure. As shown in diagram 500A, inaction 510, UE 502 may report operation cell(s) to the RAN (e.g., MN504, SN 506, and SN 508) after UE 502 selecting the operation cell(s)based on UE self-(re)selection or event-based UE self-(re)selection. UE502 may be configured with MCG, SCG#1 and SCG#2, where MN 504 is incharge of MCG, SN 506 is in charge of SCG#1, and SN 508 is in charge ofSCG#2. In method 520, UE 502 may only inform MN 504 about the selectedoperation cell(s) for Duplication (e.g., UL Duplication) in action 522.In action 524, MN 504 may inform SN 506 about the selected operationcell(s) for Duplication in SCG#1. In action 526, MN 504 may inform SN508 about the selected operation cell(s) for Duplication in SCG#2.

FIG. 5B is a diagram showing a method of a UE informing operationcell(s) for Duplication to various network nodes, in accordance with animplementation of the present disclosure. As shown in diagram 500B, inaction 510, UE 502 may report operation cell(s) to the RAN (e.g., MN504, SN 506, and SN 508) after UE 502 selecting the operation cell(s)based on UE self-(re)selection or event-based UE self-(re)selection. UE502 may be configured with MCG, SCG#1 and SCG#2, where MN 504 is incharge of MCG, SN 506 is in charge of SCG#1, and SN 508 is in charge ofSCG#2. In method 530, UE 502 may deliver the operation cell(s) forDuplication to each of the network nodes in charge of theircorresponding CGs. For example, in action 532, UE 502 may inform MN 504,when UE 502 selects one or more SCells in MCG for Duplication (e.g., ULDuplication). In action 534, UE 502 may inform SN 506, when UE 502selects one or more SCell(s) in SCG#1 for Duplication (e.g., ULDuplication). In action 536, UE 502 may inform SN 508, when UE 502selects one or more SCells in SCG#2 for Duplication (e.g., ULDuplication). After receiving information on the operation cell(s) forDuplication, the network nodes (e.g., MN 504, SN 506, or SN 508) mayknow that the Deactivation Timers of the selected operation cell(s) (orrelated CGs) may be disabled until UE 502 selects other operationcell(s) (or CG(s)). Also, in some implementations, UE 502 may also applymethod 520 or 530 to refresh the operation cell(s) when UE 502 finishesDuplication on the selected operation cell(s).

In some implementations, the Deactivation Timers are disabled on aper-CG basis (Approach#Z-2 in Table 5-1). So, the UE may not need toreport all the operation cells for Duplication to the RAN. In method 520in FIG. 5A, UE 502 may provide a bitmap to MN 504. In the bitmap, eachbit may correspond to a CG (e.g., a 3-bits bitmap; the 1^(st) bitrepresents MCG of MN 504, the 2^(nd) bit represents SCG#1 of SN 506, andthe 3^(rd) bit represents SCG#2 of SN 508). So, UE 502 may set one bitin the bitmap to “1” to indicate that all the Deactivation Timers of thecells in the corresponding CG are disabled. In contrast, UE 502 may setthe corresponding bit(s) in the bitmap=0 when no cell in a CG(s) isselected for Duplication. As such, the RAN may re-set all theDeactivation Timers of the SCells in the CG(s). In method 530 in FIG.5B, UE 502 may provide one control bit in a UL control signaling to MN504, SN 506, and/or SN 508. Based on the control bit, MN 504, SN 506,and/or SN 508 may disable (when the control bit=1) or re-set (when thecontrol bit=0) the Deactivation Timers of all SCells in thecorresponding CG(s).

Case 3: Resource Configuration for Duplication

Semi-Persistent-Scheduling (SPS) resource is radio resource that isprovided to a UE periodically. SPS resource is configured and activatedby the RAN. FIG. 6 shows a diagram of an SPS-configuration having theperiodicity provided through RRC signaling, and resource blocks for SPSresource provided through L1 signaling, in accordance with an exampleimplementation of the present disclosure. As shown in diagram 600, SPSresource appears periodically in time domain. Each SPS resource isindicated by a SPS-configuration. The SPS-configuration includes timeperiodicity (N sub-frames between two continuous SPS resource) andresource blocks (e.g., the ‘SPS’ resource blocks in the subframe whichSPS resource is located). The RAN may provide the SPS-configurationthrough dedicated signalings (e.g., the RAN configures SPS resourcethrough RRC signaling, and then activates SPS resource by L1 signalingsuch as Physical Downlink Control Channel). The UE may start using theconfigured SPS resource after RAN activating the SPS-configurationthrough L1 signaling. SPS can be applied to uplink, downlink, andsidelink direction. However, in LTE systems, SPS resource can only beapplied to special cells (e.g., PCell and PSCell).

In accordance with implementations of the present disclosure, SPSresource may be improved to support Duplication. For example, SPSresource may be applied not only to special cells but also SCells in MCGor SCGs. In addition, multiple SPS-configuration may be configured byRAN to support different numerologies (e.g., Cyclic Prefix length,sub-carrier spacing). Moreover, a UE may require multiple radio bearerswhich each of them requires Duplication. In some implementations, theRAN may separate the SPS resource allocated to different radio bearersto guarantee the QoS of each radio bearer.

In various implementations of the present disclosure, multiple resourceconfigurations may be configured to a UE for Duplication. However, theremay only be one resource configuration utilized for each cell at anygiven time.

In Case 3, some resource configurations for Duplication are based on theBase Station Explicit Signaling approach. With reference to FIG. 2, basestation 204 may provide the mapping configuration for Duplication, alongwith which the resource configuration for each cell may also beprovided. For example, base station 204 may provide MAC CE to activateDuplication to allow UE 202 to start Duplication. With reference to FIG.2, examples of the resource configuration are provided in Table 6-1. Asshown in Table 6-1, three resource configurations {RC#a-1, RC#a-2,RC#a-3} are provided to sCellIndex#2, and {RC#b-1, RC#b-2, RC#b-3} areprovided to sCellIndex#3. As such, base station 204 may further indicatewhich resource configuration UE 202 needs to apply in the MAC CE. Asdiscussed above, UE 202 may use only one resource configuration in onecell at a time. The details of {RC#a-1, RC#a-2, RC#a-3} are shown inTable 6-1, where each of {RC#a-1, RC#a-2, RC#a-3} shows a differentexample of a resource configurations.

TABLE 6-1 Under the Base Station Explicit Signaling approach, a basestation configuring at least one resource configuration to an operationcell. Resource Type LCH <-> Operation Cell Configuration DuplicationLCH#a sCellIndex#2 RC#a-1 RC#a-2 RC#a-3 CH#b CellIndex#3 RC#b-1 RC#b-2RC#b-3

TABLE 6-2 Multiple Configurations in SCellIndex#2 of Table 6-1 ResourceConfiguration in SCellIndex#2 Periodicity (by TTI or subframe) Resourceallocation RC#a-1 Period_(RC#1) represented by subframe {Resource Blocks(e.g., sf120, which means 120 ms periodicity). Configuration (RBC#1)with bitmap} RC#a-2 Ex#1: Period_(RC#2), {Resource Blocks represented bysubframe e.g., sf20, Configuration (RBC#2) which means 20 msperiodicity. without bitmap} Ex#2: TTI (Transmission Time Interval){e.g., TTI120}. UE is to calculate the periodicity by considering oneTTI = one mini-slot if mini-slot is configured to the UE. Otherwise, UEconsiders one TTI = one subframe. RC#a-3 Period_(RC#3) N.A. (gNBprovides RBC#3 in the Activation of Duplication message)

Referring to Table 6-1, for RC#a-1, the periodicity and resourceallocation are provided in the mapping configuration of RC4a-1. Theresource allocation may be represented by a bitmap and a resource blockconfiguration. FIG. 7 is a diagram of a bitmap for representing aresource configuration for Duplication, in accordance with an exampleimplementation of the present disclosure. As shown in diagram 700,Period_(RC#1) is applied to represent the periodicity of a bitmap, andoffsetRC#1 is used to represent the start of a radio frame in the systemframe, the system frame is indexed from SFN (System Frame Number) No. 0to SFN No. 1023 repeatedly in time domain, the base station (e.g., gNB)may update and deliver the SFN information in an air link. By readingthe SFN information and offsetRC#1, the UE may determine at which radioframe the bitmap starts (e.g., the starting radio frame). In addition,each radio frame can be furthered divided into 10 subframes (e.g.,Subframe#0 through Subframe#9). So, starting from the first subframe(subframe#0) of the starting radio frame, each bit in the bitmap ismapped to a corresponding subframe. A bit in the bitmap may be labeledas “1” if the corresponding subframe includes a resource block(s) forthe UE to deliver duplicated PDCP PDU packets (if any). On the otherhand, a bit in the bitmap is labeled as “0” if the correspondingsubframe does not include a resource block(s) for the UE. The radioresource of each subframe may be divided into many resource blocks. Inaddition, each resource block may have an index in the technicalspecification. So, the RAN may provide the Resource Blocks Configuration(RBC) to the UE using two indices, {RBstart, RBend}. The UE maydetermine or identify where each resource block for Duplication startsand ends. In some implementations, the bitmap may be mapped periodicallyin a radio frame to represent the resource allocations in the followingsubframes till the end of radio frame. In addition, the last mappingbitmap in the radio frame may cross the boundary of two radio frames.Thus, the last mapping bitmap may map the resource allocations ofsubframes in the next system frame until the end of the last mappingbitmap.

In some implementations, only RC#a-1 is configured for each operationcell. In such case, the UE may apply Duplication immediately based onRC#a-1 after receiving the mapping configuration for Duplication. Insome implementations, the UE may apply Duplication based on RC#a-1 onlyafter receiving an Activation of Duplication message from the basestation.

Referring back to Table 6-1, for RC#a-2, the resource allocation may beprovided through {periodicity, RBC} without using a bitmap. The RBC isprovided to the UE periodically. The base station may need to activateDuplication by delivering a dedicated signaling (e.g., an Activation ofDuplication message) to activate RC#a-2. So, RC#a-2 is valid immediatelyin the subframe where the UE receives the Activation of Duplicationmessage. Moreover, after receiving the dedicated signaling, periodicalresource may be provided to the UE on the subframe based on theperiodicity of Period_(RC#2). For example, the UE may receive adedicated signaling to activate RC#a-2 on subframe N. Thus, resourceblocks may be provided in subframe N for Duplication. Then, the nextperiodical resource for Duplication may be provided on the subframeN+Period_(RC#2)+1). So, the UE may apply the following periodicalresource automatically without a need for receiving further indicationfrom the base station. In addition, the periodical resource in thesubframe is provided through RBC (e.g., by indicating {RBstart, RBend}).

In some implementations, only RC#a-2 is configured for each operationcell in the mapping configuration. In such case, the base station maynot need to further indicate the resource configuration in theActivation of Duplication message. In some implementations, thePeriod_(RC#2) may be configured by TTI (Transmission Time Interval),which is a configurable time unit and the default value of one TTI=onesubframe. The base station may configure one TTI=one mini-slot. The timelength of a mini-slot may be X symbols, and the value X is configurable.The RAN may configure the value of X to the UE through dedicatedsignaling (e.g., RRC signaling). So, when TTI length is applied toindicate the periodicity of Resource Configuration (e.g.,Period_(RC#2)=TTI120). UE may calculate Period_(RC#2) by considering oneTTI=one subframe, if mini-slot is not configured to the UE. Otherwise,the UE may calculate Period_(RC#2) by considering one TTI=one mini-slot.

Referring back to Table 6-1, for RC#a-3, the resource allocation may beprovided through periodicity (Period_(RC#3)), which means that theresource allocation is not provided with a mapping configuration forDuplication. In this case, the base station may need to activateDuplication by delivering the Activation of Duplication message withRBC, so that RC#a-3 can be valid immediately in the subframe at whichthe UE receives the Activation of Duplication message. Moreover, afterthe Activation of Duplication message, periodical resources may beprovided to the UE to the subframe based on the periodicity ofPeriod_(RC#3), and the resource allocation is provided through RBC.

In some implementations, only RC#a-3 is configured for each operationcell in the mapping configuration. In such case, the base station mayneed not to further indicate the resource configuration in theActivation of Duplication message.

In the Base Station Explicit Signaling approach, it is possible thatmore than one resource configuration may be provided to one operationcell (as shown in Table 6-1) in the mapping configuration. In such case,the base station may need to further indicate which resourceconfiguration that the UE should follow in the Activation of Duplicationmessage by using resource block bits (RC bits) in the Activation ofDuplication message. As shown in Table 6-3, the resource configurationsin the mapping configuration may be indexed based on their sequence inthe payload. For example, in Table 6-1, RC#a-1 is the first resourceconfiguration, RC#a-2 is the second resource configuration, and so on).Then, based on the indices of the resource configurations, the RC bitsmay be provided in the Activation of Duplication message to indicate theresource configurations that the UE may use in the correspondingoperation cells. Table 6-4 provides an example format in the Activationof Duplication message. In Table 6-4, the base station may indicatewhich radio bearer that the UE may activate the Duplication function inthe PDCP layer and to what logical channels that duplicated PDCP PDUpackets are delivered in RLC layer. In addition, the operation cell(s)and resource configuration(s) for each logical channel may also beconfigured by the Operation Cell bits (OC bits) and RC bits.

TABLE 6-3 RC bits is provided to indicate the resource configurationwhich a UE should apply based on the indices of resource configurationsRC bits in Activation of Duplicatio nmessage Resource Configuration 00RC#a-1 01 RC#a-2 10 RC#a-3

TABLE 6-4 Example Activation of Duplication message in which operationcell bits and RC bits are provided to a UE Logical Operation ResourceActivation Bearer Channel Cell bits Configuration DRB ID/SRB ID LCH#a 0100 LCH#b 10 10

In ImplementationX2 and ImplementationX3 (in Table 3) of Case 1, the UEmay select the operation cell(s) based on the UE's own decision. For theresource configuration of Duplication in ImplementationX2 and/orImplementationX3, the serving base station (e.g., gNB) may provide onlyone resource configuration for each cell when the serving base stationis providing the mapping configuration to the UE, as shown in Table 6-5.So, the UE may apply the given resource configuration on the decidedoperation cell directly after the UE selects or re-selects the operationcell(s)s based on the UE's own decision.

TABLE 6-5 Example mapping configuration having {CG indices,SCellindices, Resource Configuration} provided by an MN LCH <->Operation Cell in MC scenario Resource Configura- Type CG index LCH Cellindex tion DL MCG index LCH#a ServCellIndex#1 RC#a-1 Duplication(=sCellIndex#1) SCG#1 index LCH#b ServCellIndex#2 RC#a-2 (=sCellIndex#2)SCG#2 index LCH#c ServCellIndex#3 RC#a-3 (=sCellIndex#3) UL MCG indexLCH#m ServCellIndex# 0 RC#a-1 Duplication (“0000”(PCell)) SCG#1 indexLCH#n ServCellIndex#4 RC#a-3 (=sCellIndex#4)

In some implementations, the RAN may require the UE to send a BufferStatus Report (BSR) for the RAN to decide the dedicated resource for theUE to deliver duplicated PDCP PDU packets. For the BSR, the RAN mayconfigure the logical channel groups (LCGs) to each UE. Each LCG is agroup of logical channels whose pending packets amount may beaccumulated in one LCG in the BSR. Thus, the UE may only report thebuffer status of each LCG instead of each of the logical channels. TheDuplication process may affect the BSR since the logical channels may beactivated and/or deactivated occasionally.

FIG. 8 is a diagram illustrating a RAN providing mappings between LCHsand LCGs for BSR, in accordance with an example implementation of thepresent disclosure. As shown in diagram 800, the Duplication function ofRadio bearer#K is activated. Before the activation of Duplication, thepackets of Radio bearer#K is delivered to LCH#6. Then, the duplicatedPDCP PDU packets may be delivered to LCH6 and LCH#7 after theDuplication is activated. So, after the Duplication is activated, theRAN may need to re-indicate the LCG of the UE since the LCH isactivated. In addition, when Duplication of a radio bearer is activated,LCH#7 is activated, thus packets are forwarded to LCH#7. Then, a new BSRprocess may be triggered when new packets arrive at the buffer of LCH#7.However, since the amount of the pending packets in LCH#7 issubstantially the same as the amount of the pending packets in LCH#6,the RAN may obtain the buffer status of the pending packets in LCH#7 byreceiving the buffer status of LCH#6. Thus, a new BSR may not benecessary.

Although Duplication may affect LCGs and/or BSR, the impact ofDuplication on BSR may be reduced by the following mechanisms describedbelow.

In the present implementation, a radio bearer which is originally mappedto the original logical channel (e.g., LCH#O). A duplicated logicalchannel (LCH#D) is activated to deliver duplicated PDCP PDU packets. Inthe present implementation, the base station does not provide additionalLCG information for LCH#D. LCH#D may be regarded as with the same LCG asthe LCH#O, since both LCH#O and LCH#D both carry substantially the sameduplicated PDCP PDU packages. In addition, LCH#D does not activate theBSR process. To the radio bearer, the BSR process is triggered andreported based on LCH#O.

In the present implementation, a special BSR format is provided for theUE to report the buffer size of LCH#O. After receiving the special BSRfor Duplication, the RAN may know that both LCH#O and LCH#D have pendingpackets to transmit. FIG. 9 is a diagram illustrating a special BSR forDuplication, in accordance with an example implementation of the presentdisclosure. As shown in diagram 900, a special BSR for Duplicationincludes a MAC header and a payload, which includes an LCH ID and abuffer size of LCH#O. The base station may differentiate the special BSRfor Duplication from other MAC CEs by reading the MAC header (e.g., adifferent Logical Channel ID (LCID) is configured for the special BSRfor Duplication). After reading the MAC header, the base station mayidentify the LCH ID of LCH#O. The pending packets of LCH#O may beprovided in the payload of the special BSR for Duplication. In addition,the base station may ascertain or know that there are also pendingpackets in the LCH#D.

In the present implementation, after receiving the special BSR forDuplication, the base station may need to provide UL radio resources forUE to deliver the pending packets in LCH#O and LCH#D. In someimplementations, the base station may utilize cross-carrier schedulingin the UL resource allocation to achieve frequency diversity.

FIG. 10 is a diagram illustrating cross-carrier scheduling forDuplication, where the mapping between logical channels and cells arepre-defined by a base station, in accordance with an exampleimplementation of the present disclosure. As shown in diagram 1000, thebase station may provide a UL resource grant on the DL PCell PDCCH(Physical Downlink Control Channel). The UL grant for the UE may includethe UL grant for LCH#O and LCH#D, which are located on PCell (UL) andSCell#1 (UL), respectively. Moreover, the mapping between LCH#O andPCell, and between LCH#D and SCell#1, is already configured by the RANbased on Case 1 above. Thus, after receiving the UL grant from the basestation, the UE may know what the resource on PCell (UL) may be utilizedto deliver the pending packets of LCH#O, and the resource on SCell#1(UL) may be utilized to deliver the pending packets of LCH#D.

It should be understood that the special BSR for Duplication and the ULgrant approaches can also be applied to CA, DC (e.g., MN or SN canconfigure BSR and provide UL resources independently), and MCoperations.

FIG. 11 illustrates a block diagram of a node for wirelesscommunication, in accordance with various aspects of the presentdisclosure. As shown in FIG. 11, node 1100 may include a transceiver1120, a processor 1126, a memory 1128, one or more presentationcomponents 1134, and at least one antenna 1136. The node 1100 may alsoinclude an Radio Frequency (RF) spectrum band module, a base stationcommunications module, a network communications module, and a systemcommunications management module, input/output (I/O) ports, I/Ocomponents, and power supply (not explicitly shown in FIG. 11). Each ofthese components may be in communication with each other, directly orindirectly, over one or more buses 1140.

The transceiver 1120 having a transmitter 1122 and a receiver 1124 maybe configured to transmit and/or receive time and/or frequency resourcepartitioning information. In some implementations, the transceiver 1120may be configured to transmit in different types of subframes and slotsincluding, but not limited to, usable, non-usable and flexibly usablesubframes and slot formats. The transceiver 1120 may be configured toreceive data and control channels.

The node 1100 may include a variety of computer-readable media.Computer-readable media can be any available media that can be accessedby the node 1100 and include both volatile and non-volatile media,removable and non-removable media. By way of example, and notlimitation, computer-readable media may comprise computer storage mediaand communication media. Computer storage media includes both volatileand non-volatile, removable and non-removable media implemented in anymethod or technology for storage of information such ascomputer-readable instructions, data structures, program modules orother data.

Computer storage media includes RAM, ROM, EEPROM, flash memory or othermemory technology, CD-ROM, digital versatile disks (DVD) or otheroptical disk storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices. Computer storage media doesnot comprise a propagated data signal. Communication media typicallyembodies computer-readable instructions, data structures, programmodules or other data in a modulated data signal such as a carrier waveor other transport mechanism and includes any information deliverymedia. The term “modulated data signal” means a signal that has one ormore of its characteristics set or changed in such a manner as to encodeinformation in the signal. By way of example, and not limitation,communication media includes wired media such as a wired network ordirect-wired connection, and wireless media such as acoustic, RF,infrared and other wireless media. Combinations of any of the aboveshould also be included within the scope of computer-readable media.

The memory 1128 may include computer-storage media in the form ofvolatile and/or non-volatile memory. The memory 1128 may be removable,non-removable, or a combination thereof. Example memory includessolid-state memory, hard drives, optical-disc drives, and etc. Asillustrated in FIG. 11, The memory 1128 may store computer-readable,computer-executable instructions 1132 (e.g., software codes) that areconfigured to, when executed, cause the processor 1126 to performvarious functions described herein, for example, with reference to FIGS.1 through 10. Alternatively, the instructions 1132 may not be directlyexecutable by the processor 1126 but be configured to cause the node1100 (e.g., when compiled and executed) to perform various functionsdescribed herein.

The processor 1126 may include an intelligent hardware device, e.g., acentral processing unit (CPU), a microcontroller, an ASIC, and etc. Theprocessor 1126 may include memory. The processor 1126 may process thedata 1130 and the instructions 1132 received from the memory 1128, andinformation through the transceiver 1120, the base band communicationsmodule, and/or the network communications module. The processor 1126 mayalso process information to be sent to the transceiver 1120 fortransmission through the antenna 1136, to the network communicationsmodule for transmission to a core network.

One or more presentation components 1134 presents data indications to aperson or other device. Example presentation components 1134 include adisplay device, speaker, printing component, vibrating component, andetc.

From the above description it is manifest that various techniques can beused for implementing the concepts described in the present disclosurewithout departing from the scope of those concepts. Moreover, while theconcepts have been described with specific reference to certainimplementations, a person of ordinary skill in the art would recognizethat changes can be made in form and detail without departing from thescope of those concepts. As such, the described implementations are tobe considered in all respects as illustrative and not restrictive. Itshould also be understood that the present disclosure is not limited tothe particular implementations described above, but many rearrangements,modifications, and substitutions are possible without departing from thescope of the present disclosure.

What is claimed is:
 1. A method by a wireless communication network forhandling one or more duplicated packet data convergence protocol (PDCP)packets, the method comprising: sending, by a master node, a request fora configuration for duplication to a secondary node; providing, by asecondary node, a mapping configuration for duplication in a secondarycell group (SCG) to a user equipment (UE).
 2. The method of claim 1,further comprising: configuring, by the secondary node, one or moreallowed serving cells in the SCG for receiving the one or moreduplicated PDCP packets, the one or more allowed serving cells includingat least one of a primary secondary cell (PSCell) and one or moresecondary cells (SCells) of the secondary node.
 3. The method of claim2, wherein the mapping configuration provides mapping rules between oneor more logical channels and the one or more allowed serving cells. 4.The method of claim 2, wherein the mapping configuration provides one ormore Serving Cell indices corresponding to the one or more allowedserving cells for receiving the one or more duplicated PDCP packets. 5.The method of claim 4, wherein a Serving Cell index value=0 is mapped tothe PSCell in the SCG corresponding to at least one logical channelthrough which the UE is allowed to deliver the one or more duplicatedPDCP packets.
 6. The method of claim 1, wherein: the mappingconfiguration for duplication in the SCG includes information of atleast one physical radio resource block on one or more allowed servingcells for receiving the one or more duplicated PDCP packets from the UE.7. The method of claim 1, further comprising: sending, by the secondarynode, an activation message of packet duplication to the UE to activateat least one logical channel corresponding to at least one radio bearerfor the UE to deliver the one or more duplicated PDCP packets.
 8. Themethod of claim 7, further comprising: receiving, by the secondary node,the one or more duplicated PDCP packets in the at least one logicalchannel corresponding to the at least one radio bearer for the UE. 9.The method of claim 7, further comprising: sending, by the secondarynode, a deactivation message of packet duplication to the UE to stop theUE from applying one or more allowed serving cells in the SCG to the atleast one logical channel.
 10. The method of claim 1, furthercomprising: providing, by the master node, a mapping configuration forduplication in a master cell group (MCG) to the UE.
 11. The method ofclaim 10, further comprising: configuring, by the master node, one ormore allowed serving cells in the MCG for receiving the one or moreduplicated PDCP packets, the one or more allowed serving cells includingat least one of a primary cell (PCell) and one or more secondary cells(S Cells) of the master node.
 12. The method of claim 10, wherein themapping configuration provides mapping rules between one or more logicalchannels and the one or more allowed serving cells.
 13. The method ofclaim 10, wherein the mapping configuration provides one or more ServingCell indices corresponding to the one or more allowed serving cells forreceiving the one or more duplicated PDCP packets.
 14. The method ofclaim 13, wherein a Serving Cell index value=0 is mapped to the PCell inthe MCG corresponding to at least one logical channel through which theUE is allowed to deliver the one or more duplicated PDCP packets. 15.The method of claim 10, wherein: the mapping configuration forduplication in the MCG includes information of at least one physicalradio resource block on one or more allowed serving cells for receivingthe one or more duplicated PDCP packets from the UE.
 16. The method ofclaim 10, further comprising: sending, by the master node, an activationmessage of packet duplication to the UE to activate at least one logicalchannel corresponding to at least one radio bearer for the UE to deliverthe one or more duplicated PDCP packets.
 17. The method of claim 16,further comprising: receiving, by the master node, the one or moreduplicated PDCP packets in the at least one logical channelcorresponding to the at least one radio bearer for the UE.
 18. Themethod of claim 16, further comprising: sending, by the master node, adeactivation message of packet duplication to the UE to stop the UE fromapplying one or more allowed serving cells in the MCG to the at leastone logical channel.